Organic electroluminescence device

ABSTRACT

An organic electroluminescence device which exhibits an excellent purity of color and a high efficiency of light emission, has a long life and emits reddish light and a novel compound having these characteristics are provided.  
     The organic electroluminescence device comprises an organic layer disposed between at least one pair of electrodes, wherein the organic layer comprises a compound having a fluoranthene skeleton structure substituted at least with an amine group or an alkenyl group.

TECHNICAL FIELD

[0001] The present invention relates to an organic electroluminescencedevice which is used as a light source such as a planar light emittingmember of televisions and a back light of displays, exhibits anexcellent purity of color and a high efficiency of light emission, has along life and emits reddish light and to a novel compound having thesecharacteristics.

BACKGROUND ART

[0002] Electroluminescence (referred to as EL, hereinafter) devicesusing organic compounds are expected to be used for inexpensive fullcolor display devices of the solid light emission type which can displaya large area and development thereof has been actively conducted. Ingeneral, an EL device is constituted with a light emitting layer and apair of electrodes faced to each other at both sides of the lightemitting layer. When a voltage is applied between the electrodes,electrons are injected at the side of the cathode and holes are injectedat the side of the anode. The electrons are combined with the holes inthe light emitting layer and an excited state is formed. When theexcited state returns to the normal state, the energy is emitted aslight.

[0003] Although the practical application of organic EL devices hasstarted recently, devices for full color displays are still underdevelopment. In particular, a material for organic EL devices whichexhibits an excellent purity of color and a high efficiency of lightemission, has a long life and emits reddish light has been desired.

[0004] In an attempt to satisfy the above desire, a device emitting redlight in which a derivative of naphthacene or pentacene is added to alight emitting layer is disclosed in Japanese Patent ApplicationLaid-Open No. Heisei 8(1996)-311442. Although this device exhibits anexcellent purity of red light, the device exhibits an efficiency oflight emission as low as 0.7 lm/W and has an insufficient average lifewhich is shorter than 150 hours. An average life of at least severalthousand hours is necessary for practical applications. A device inwhich a compound derived from dicyanomethylene (DCM) is added to a lightemitting layer is disclosed in Japanese Patent Application Laid-Open No.Heisei 3(1991)-162481. However, this device exhibits an insufficientpurity of red light. In Japanese Patent Application Laid-Open Nos.Heisei 10(1998)-340782 and Heisei 11(1999)-40360, organic EL devicesusing fluoranthene compounds are disclosed. However, the devices usingthe compounds disclosed in the above patent applications do not emityellow to red light. The efficiency of light emission is as small as 4cd/A or smaller and insufficient.

DISCLOSURE OF THE INVENTION

[0005] The present invention has been made to overcome the aboveproblems and has an object of providing an organic EL device whichexhibits an excellent purity of color and a high efficiency of lightemission, has a long life and emits reddish light and a novel compoundhaving these characteristics.

[0006] As the result of extensive studies by the present inventors todevelop an organic electroluminescence device (referred to as an organicEL device, hereinafter) having the above advantageous properties, it wasfound that the object can be achieved by using a compound having afluoranthene skeleton structure substituted at least with an amine groupor an alkenyl group as the light emitting material.

[0007] The organic electroluminescence device of the present inventioncomprises an organic layer disposed between at least one pair ofelectrodes, wherein the organic layer comprises a compound having afluoranthene skeleton structure substituted at least with an amine groupor an alkenyl group.

[0008] It is preferable that the above compound is a compound selectedfrom compounds represented by the following general formulae [1] to[18]:

[0009] wherein X¹ to X²⁰ each independently represents hydrogen atom, alinear, branched or cyclic alkyl group having 1 to 20 carbon atoms, alinear, branched or cyclic alkoxy group having 1 to 20 carbon atoms, asubstituted or unsubstituted aryl group having 6 to 30 carbon atoms, asubstituted or unsubstituted aryloxy group having 6 to 30 carbon groups,a substituted or unsubstituted arylamino group having 6 to 30 carbonatoms, a substituted or unsubstituted alkylamino group having 1 to 30carbon atoms, a substituted or unsubstituted arylalkylamino group having7 to 30 carbon atoms or a substituted or unsubstituted alkenyl groupshaving 8 to 30 carbon atoms; a pair of adjacent groups represented by X¹to X²⁰ and a pair of adjacent substituents to groups represented by X¹to X²⁰ may form a cyclic structure in combination; when a pair ofadjacent substituents are aryl groups, the pair of substituents may be asingle group; and at least one of substituents represented by X¹ toX^(i), i representing a number of 12 to 20, comprises an amine group oran alkenyl group;

[0010] wherein R¹ to R⁴ each independently represent an alkyl grouphaving 1 to 20 carbon atoms or a substituted or unsubstituted aryl grouphaving 6 to 30 carbon atoms; in one or both of a pair of groupsrepresented by R¹ and R² and a pair of groups represented by R³ and R⁴,the groups forming the pair may be bonded through —O— or —S—; R⁵ to R¹⁶represents hydrogen atom, a linear, branched or cyclic alkyl grouphaving 1 to 20 carbon atoms, a linear, branched or cyclic alkoxy grouphaving 1 to 20 carbon atoms, a substituted or unsubstituted aryl grouphaving 6 to 30 carbon atoms, a substituted or unsubstituted aryloxygroup having 6 to 30 carbon groups, a substituted or unsubstitutedarylamino group having 6 to 30 carbon atoms, a substituted orunsubstituted alkylamino group having 1 to 30 carbon atoms, asubstituted or unsubstituted arylalkylamino group having 7 to 30 carbonatoms or a substituted or unsubstituted alkenyl groups having 8 to 30carbon atoms; a pair of adjacent groups represented by R⁵ to R¹⁶ and apair of adjacent substituents to groups represented by R⁵ to R¹⁶ mayform a cyclic structure in combination; and at least one of substituentsrepresented by R⁵ to R¹⁶ comprises an amine group or an alkenyl group.

[0011] The novel compound of the present invention is a compoundrepresented by any of the above general formulae [1] to [18].

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 shows the ¹H-NMR spectrum of an example of the novelcompound of the present invention.

[0013]FIG. 2 shows the ¹H-NMR spectrum of another example of the novelcompound of the present invention.

[0014]FIG. 3 shows the ¹H-NMR spectrum of still another example of thenovel compound of the present invention.

THE MOST PREFERRED EMBODIMENT TO CARRY OUT THE INVENTION

[0015] The organic electroluminescence device of the present inventioncomprises an organic layer disposed between at least one pair ofelectrodes, wherein the organic layer comprises compounds having afluoranthene skeleton structure substituted at least with an amine groupor an alkenyl group.

[0016] This compound is a novel compound and is represented by any ofthe above general formulae [1] to [18].

[0017] In general formulae [1] to [16], X¹ to X²⁰ each independentlyrepresents hydrogen atom, a linear, branched or cyclic alkyl grouphaving 1 to 20 carbon atoms, a linear, branched or cyclic alkoxy grouphaving 1 to 20 carbon atoms, a substituted or unsubstituted aryl grouphaving 6 to 30 carbon atoms, a substituted or unsubstituted aryloxygroup having 6 to 30 carbon groups, a substituted or unsubstitutedarylamino group having 6 to 30 carbon atoms, a substituted orunsubstituted alkylamino group having 1 to 30 carbon atoms, asubstituted or unsubstituted arylalkylamino group having 7 to 30 carbonatoms or a substituted or unsubstituted alkenyl groups having 8 to 30carbon atoms; a pair of adjacent groups represented by X¹ to X²⁰ and apair of adjacent substituents to groups represented by X¹ to X²⁰ mayform a cyclic structure in combination; when a pair of adjacentsubstituents are aryl groups, the pair of substituents may be a singlegroup; and at least one of substituents represented by X¹ to X^(i), irepresenting a number of 12 to 20, comprises an amine group or analkenyl group. That a pair of adjacent substituents may be a singlegroup when the pair of adjacent substituents are aryl groups means thatthe adjacent bonds for the pair of substituents are bonded to the samesingle divalent aromatic ring group.

[0018] In general formulae [17] and [18], R¹ to R⁴ each independentlyrepresent an alkyl group having 1 to 20 carbon atoms or a substituted orunsubstituted aryl group having 6 to 30 carbon atoms; in one or both ofa pair of groups represented by R¹ and R2 and a pair of groupsrepresented by R³ and R⁴, the groups forming the pair may be bondedthrough —O— or —S—; R⁵ to R¹⁶ represents hydrogen atom, a linear,branched or cyclic alkyl group having 1 to 20 carbon atoms, a linear,branched or cyclic alkoxy group having 1 to 20 carbon atoms, asubstituted or unsubstituted aryl group having 6 to 30 carbon atoms, asubstituted or unsubstituted aryloxy group having 6 to 30 carbon groups,a substituted or unsubstituted arylamino group having 6 to 30 carbonatoms, a substituted or unsubstituted alkylamino group having 1 to 30carbon atoms, a substituted or unsubstituted arylalkylamino group having7 to 30 carbon atoms or a substituted or unsubstituted alkenyl groupshaving 8 to 30 carbon atoms; a pair of adjacent groups represented by R⁵to R¹⁶ and a pair of adjacent substituents to groups represented by R⁵to R¹⁶ may form a cyclic structure in combination; and at least one ofsubstituents represented by R⁵ to R¹⁶ comprises an amine group or analkenyl group.

[0019] Preferable compounds among the compounds represented by generalformulae [1] to [18] are shown in the following.

[0020] It is preferable that the fluoranthene skeleton structurecomprises at least 5 condensed rings and more preferably at least 6condensed rings. By using the compounds having this structure, lighthaving a longer wave length such as yellowish to reddish light can beemitted.

[0021] It is preferable that the fluoranthene skeleton structure issubstituted with an amino group. By using the compound having thisstructure, a light emitting material having a longer life can beobtained.

[0022] It is preferable that the amino group is a substituted orunsubstituted arylamino group and more preferably a substituted orunsubstituted diarylamino group. By using the compound having thisstructure, a device showing a smaller decrease in the light emission atincreased concentrations of the compound and exhibiting a highefficiency can be obtained even when the above compound is added to thelight emitting layer in a concentration as high as 2% or higher.

[0023] It is preferable that the above compound has a symmetricstructure having an axial symmetry or a symmetry with respect to plane.By using the compound having this structure, durability of the device isimproved and the quantum efficiency of fluorescence is enhanced.

[0024] It is preferable that the above compound has at least tensix-membered rings or five-membered rings. The compound has a glasstransition temperature of 100° C. or higher due to this structure andheat stability of a layer composed of or comprising this compound isimproved. It is preferable that the above compound has an aryl group, acyclic alkyl group, an aryloxy group, an arylthio group or an arylalkylgroup each having 4 or more carbon atoms. Since these groups exhibitsteric hindrance and the decrease in the light emission at increasedconcentrations of the compound can be prevented.

[0025] It is preferable that, in general formulae [17] and [18], R¹⁵ andR⁹ each represent a group having a substituent. When the compoundrepresented by general formula [17] or [18] has this structure, thecompound has an improved stability against oxidation and reduction andthe life of the device can be extended.

[0026] When the fluoranthene skeleton structure is substituted with twoamino groups, two alkenyl groups or a combination of an amino group andan alkenyl group, the compound having this fluoranthene skeletonstructure has isomers.

[0027] Examples of the isomers are described in the case where thefluoranthene skeleton structure is7,14-diphenylacenaphtho[1,2-k]-fluoranthene.

[0028] Dibromo-substituted acenaphtho[1,2-k]fluoranthene has twoisomers, i.e., 3,10-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthene(isomer A) and 3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthene(isomer B).

[0029] The final product obtained from isomer A and isomer B as theintermediates contains an amino-substituted compound derived from isomerA and an amino-substituted compound derived from isomer B. When thefinal product is prepared, the relative amounts of isomer A and isomer Bcontained in the final product is different depending on the process ofthe preparation. (1) The dibromo-substituted compounds may be obtainedfrom a solution portion of a reaction mixture in which thedibromo-substituted compounds are dissolved. (2) The dibromo-substitutedcompounds may also be obtained from precipitates formed byrecrystallization from a solution which is obtained by dissolving theproduct obtained above from the solution portion of the reactionmixture. (3) The dibromo-substituted compounds may also be obtained fromthe solution left after the above recrystallization. By suitablyselecting the process and the type of the solvent used for thetreatment, the object compound containing various amounts of isomer Aand isomer B and, specifically, having a ratio of the amount by mole ofisomer A to the amount in mole of isomer B in the range of 10:90 to90:10, can be obtained.

[0030] It is preferable that the error in the ratio of the amounts bymole of the isomers is: (i) isomer A:isomer B=x±10:y±10 (x±y=100) andmore preferably (ii) isomer A:isomer B=x±5:y±5 (x±y=100). When therelation (i) is satisfied, the ratio of the amounts of the isomers willbe described as approximately constant and, when the relation (ii) issatisfied, the ratio of the amounts of the isomers will be described asconstant, hereinafter.

[0031] When the above compound of the present invention has isomers, aplurality of isomers can be comprised in the organic layer. It ispreferable that the device is prepared under the condition that theratio of the amounts of the isomers is kept approximately constant orconstant. By preparing the device in this manner, the spectrum of thelight emitted from the device can be kept the same. In other words, thecolor of the emitted light can be kept the same. Moreover, the color ofthe emitted light can be changed by changing the ratio of the amounts ofthe isomers. Naturally, the organic layer may comprise a single compoundwith exclusion of any other isomers.

[0032] When a compound contains isomers as described above, one of theisomers can emit light having a longer wavelength than that of lightemitted from other isomers. Therefore, light having a longer wavelengthsuch red light can be emitted when the ratio of the amount by mole ofthe isomer which can emit light having a longer wavelength to the amountby mole of the isomer which can emit light having a shorter wavelengthis preferably in the range of 90:10 to 60:40 and more preferably in therange of 99:1 to 70:30.

[0033] Taking advantage of the difference in the chemical shift in¹H-NMR between the isomers, the ratio of the amounts of the isomers canbe calculated from the ratio of the areas of peak signals assigned toeach isomer.

[0034] It is preferable that the organic layer is at least one of a holetransportation layer and a light emitting layer.

[0035] A layer of an inorganic compound may be disposed between theorganic layer and the electrode.

[0036] The organic EL device of the present invention emits reddishlight.

[0037] Examples of the compounds represented by general formulae [1] to[18] of the present invention include (A-1) to (A-18) and (B-1) to(B-17) which are shown in the following. However, the present inventionis not limited to these compounds shown as the examples. In the formulaeshown in the following, Me means methyl group and Et means ethyl group.

[0038] Since the compound used for the organic EL device of the presentinvention has the fluoranthene skeleton structure substituted with anamine group or an alkenyl group, the compound exhibits a high yield offluorescence and emits reddish or yellowish light. Therefore, theorganic EL device using this compound emits reddish to yellowish light,exhibits a high efficiency of light emission and has a long life.

[0039] The organic EL device of the present invention is a device inwhich one or a plurality of organic thin films are disposed between ananode and a cathode. When the device has a single organic layer, a lightemitting layer is disposed between an anode and a cathode. The lightemitting layer contains a light emitting material and may also contain ahole injecting material to transport holes injected at the anode to thelight emitting material or an electron injecting material to transportelectrons injected at the cathode to the light emitting material. It ispreferable that the light emitting layer is formed with a light emittingmaterial having a very high quantum efficiency of fluorescence emissionand excellent ability to transfer holes and electrons and a uniform thinfilm is formed. The organic EL device having a multi-layer structure hasa laminate structure such as: (an anode/a hole injecting layer/a lightemitting layer/a cathode), (an anode/a light emitting layer/an electroninjecting layer/a cathode) and (an anode/a hole injecting layer/a lightemitting layer/an electron injecting layer/a cathode).

[0040] In the light emitting layer, where necessary, conventional lightemitting materials, doping materials, hole injecting materials andelectron injecting materials may be used in addition to the compoundrepresented by any of general formulae [1] to [18] of the presentinvention. It is preferable that these compounds are added to any of thelight emitting layer, the electron injecting layer, the holetransporting layer or the hole injecting layer in a concentration of 1to 70% by weight and more preferably in a concentration of 1 to 20% byweight. In particular, it is preferable that the compound of the presentinvention is used as the doping material.

[0041] Deterioration in the luminance and the life caused by quenchingcan be prevented by the multi-layer structure of the organic EL. Wherenecessary, light emitting materials, other doping materials, holeinjecting materials and electron injecting materials may be used incombination. By using other doping materials, the luminance and theefficiency of light emission can be improved and red light and whitelight can be emitted. The hole injecting layer, the light emitting layerand the electron injecting layer may each have a multi-layer structurehaving two or more layers. When the hole injecting layer has amulti-layer structure, the layer into which holes are injected from theelectrode is referred to as the hole injecting layer and the layer whichreceives holes from the hole injecting layer and transports holes fromthe hole injecting layer to the light emitting layer is referred to asthe hole transporting layer. When the electron injecting layer has amulti-layer structure, the layer into which electrons are injected fromthe electrode is referred to as the electron injecting layer and thelayer which receives electrons from the electron injecting layer andtransports electrons from the electron injecting layer to the lightemitting layer is referred to as the electron transporting layer. Theselayers are each selected and used in accordance with factors such as theenergy level, heat resistance and adhesion with the organic layers orthe metal electrodes of the material.

[0042] Examples of the material which can be used in the organic layeras the light emitting material or the host material in combination withthe compound represented by any of general formulae [1] to [18] includeanthracene, naphthalene, phenanthrene, pyrene, tetracene, coronene,chrysene, fluoresceine, perylene, phthaloperylene, naphthaloperylene,perynone, phthaloperynone, naphthaloperynone, diphenylbutadiene,tetraphenylbutadiene, coumarine, oxadiazole, aldazine, bisbenzoxazoline,bisstyryl, pyrazine, cyclopentadiene, metal complexes of quinoline,metal complexes of aminoquinoline, metal complexes of benzoquinoline,imines, diphenylethylene, vinylanthracene, diaminocarbazole, pyrane,thiopyrane, polymethine, merocyanine, chelates of oxinoid compounds withimidazoles, quinacridone, rubrene, stilbene derivatives and fluorescentpigments. However, the above material is not limited to the compoundsdescribed above as the examples.

[0043] As the hole injecting material, a compound which has the abilityto transfer holes, exhibits an excellent effect of hole injection fromthe anode and an excellent effect of hole injection to the lightemitting layer or the light emitting material, prevents transfer ofexcited components formed in the light emitting layer into the electroninjecting layer or the electron injecting material and has excellentability to form a thin film is preferable. Examples of the abovecompound include phthalocyanine derivatives, naphthalocyaninederivatives, porphyrin derivatives, oxazole, oxadiazole, triazole,imidazole, imidazolone, imdazolethione, pyrazoline, pyrazolone,tetrahydroimidazole, oxazole, oxadiazole, hydrazone, acylhydrazone,polyarylalkanes, stilbene, butadiene, triphenylamines of thebenzidine-type, triphenylamines of the styrylamine type, triphenylaminesof the diamine type, derivatives of these compounds and macromolecularcompounds such as polyvinylcarbazole, polysilane and conductivemacromolecules. However, the above compound is not limited to thecompounds described above as the examples.

[0044] Among the hole injection materials which can be used in theorganic EL device of the present invention, aromatic tertiary aminederivatives and phthalocyanine derivatives are more effective.

[0045] Examples of the aromatic tertiary amine derivative includetriphenylamine, tritolylamine, tolyldiphenylamine,N,N′-diphenyl-N,N′-(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine,N,N,N′,N′-(4-methylphenyl)-1,1′-phenyl-4,4′-diamine,N,N,N′,N′-(4-methylphenyl)-1,1′-biphenyl-4,4′-diamine,N,N′-diphenyl-N,N′-dinaphthyl-1,1′-biphenyl-4,4′-diamine,N,N′-(methylphenyl)-N,N′-(4-n-butylphenyl)phenanthrene-9,10-diamine,N,N-bis(4-di-4-tolylaminophenyl)-4-phenylcyclohexane and oligomers andpolymers having a skeleton structure of these aromatic tertiary amines.However, the aromatic tertiary amine derivative is not limited to thecompounds described above as the examples.

[0046] Examples of the phthalocyanine (Pc) derivative include H₂Pc,CuPc, CoPc, NiPc, ZnPc, PdPc, FePc, MnPc, ClAlPc, ClGaPc, ClInPc,ClSnPc, Cl₂SiPc, (HO)AlPc, (HO)GaPc, VOPc, TiOPc, MoOPc, GaPc-O-GaPc andcorresponding derivatives of naphthalocyanine. However, the derivativesof phthalocyanine and naphthalocyanine are not limited to the compoundsdescribed above as the examples.

[0047] As the electron injecting material, a compound which has theability to transport electrons, exhibits an excellent effect of electroninjection from the cathode and an excellent effect of electron injectionto the light emitting layer or the light emitting material, preventstransfer of excited components formed in the light emitting layer intothe hole injecting layer and has excellent ability to form a thin filmis preferable. Examples of the above compound include fluorenone,anthraquinodimethane, diphenoquinone, thiopyrane dioxide, oxazole,oxadiazole, triazole, imidazole, peryleneteteracarboxylic acid,fluorenylidenemethane, anthraquinodimethane, anthrone and derivatives ofthese compounds. However, the above compound is not limited to thecompounds described above as the examples. The charge injecting propertycan be improved by adding an electron accepting material to the holeinjecting material or by adding an electron donating material to theelectron injecting material.

[0048] In the organic EL device of the present invention, more effectiveelectron injecting materials are metal complex compounds andfive-membered derivatives containing nitrogen.

[0049] Examples of the metal complex compound include8-hydroxy-quinolinatolithium, bis(8-hydroxyquinolinato)zinc,bis(8-hydroxy-quinolinato)copper, bis(8-hydroxyquinolinato)manganese,tris(8-hydroxy-quinolinato)aluminum,tris(2-methyl-8-hydroxyquinolinato)aluminum,tris(8-hydroxyquinilinato)gallium,bis(10-hydroxybenzo[h]quinolinato)beryllium,bis(10-hydroxybenzo[h]quinolinato)zinc,bis(2-methyl-8-quinolinato)chlorogallium,bis(2-methyl-8-quinolinato)(o-cresolato)gallium,bis(2-methyl-8-quinolinato)(1-naphtholato)aluminum andbis(2-methyl-8-quinolinato)(2-naphtholato)gallium. However, the metalcomplex compound is not limited to the compounds described above as theexamples.

[0050] Preferable examples of the five-membered derivative containingnitrogen include derivatives of oxazoles, thiazoles, thiadiazoles andtriazoles. Specific examples include 2,5-bis(1-phenyl)-1,3,4-oxazole,dimethylPOPOP, 2,5-bis(1-phenyl)-1,3,4-thiazole,2,5-bis(1-phenyl)-1,3,4-oxadiazole,2-(4′-tert-butylphenyl)-5-(4″-biphenyl)-1,3,4-oxadiazole,2,5-bis(1-naphthyl)-1,3,4-oxadiazole,1,4-bis[2-(5-phenyloxadiazolyl)]benzene,1,4-bis[2-(5-phenyloxadiazolyl)-4-tert-butylbenzene],2-(4′-tert-butylphenyl)-5-(4″-biphenyl)-1,3,4-thiadiazole,2,5-bis(1-naphthyl)-1,3,4-thiadiazole,1,4-bis[2-(5-phenylthiadiazolyl)]benzene,2-(4′tert-butylphenyl)-5-(4″-biphenyl)-1,3,4-triazole,2,5-bis(1-naphthyl)-1,3,4-triazole and1,4-bis[2-(5-phenyltriazolyl)]benzene. However, the five-memberedderivative containing nitrogen is not limited to the compounds describedabove as the examples.

[0051] In the organic EL device of the present invention, the organiclayer may contain at least one of light emitting materials, dopingmaterials, hole injecting materials and electron injecting materials inthe same layer in addition to the compound represented by any of generalformulae [1] to [18]. In order to improve stability of the organic ELdevice of the present invention with respect to the temperature, thehumidity and the atmosphere, a protecting layer may be formed on thesurface of the device or the entire device may be protected with siliconoil or a resin.

[0052] As the conductive material used for the anode of the organic ELdevice, a material having a work function of 4 eV or greater issuitable. Examples of such a material include carbon, aluminum,vanadium, iron, cobalt, nickel, tungsten, silver, gold, platinum,palladium, alloys of these metals, metal oxides used for ITO substratesand NESA substrates such as tin oxide and indium oxide and organicconductive resins such as polythiophene and polypyrrol. As theconductive material used for the cathode, a material having a workfunction smaller than 4 eV is suitable. Examples of such a materialinclude magnesium, calcium, tin, lead, titanium, yttrium, lithium,ruthenium, manganese, aluminum and alloys of these metals. However, thematerials used for the anode and the cathode are not limited to thematerials described above as the examples. Typical examples of the alloyinclude alloys of magnesium and silver, alloys of magnesium and indiumand alloys of lithium and aluminum. However, the alloy is not limited tothese alloys described as the examples. The composition of the alloy iscontrolled by the temperature of the source of vapor deposition, theatmosphere and the degree of vacuum and can be adjusted suitably. Theanode and the cathode may have a multi-layer structure having two ormore layers, where necessary.

[0053] In the organic EL device of the present invention, it ispreferable that a layer of a chalcogenide, a metal halide or a metaloxide (this layer may occasionally be referred to as a surface layer) isdisposed on the surface of at least one of the pair of electrodesprepared as described above. Specifically, it is preferable that a layerof a chalcogenide (including an oxide) of a metal such as silicon andaluminum is disposed on the surface of the anode at the side of thelayer of the light emitting medium and a layer of a metal halide or ametal oxide is disposed on the surface of the cathode at the side of thelayer of the light emitting medium. Due to the above layers, stabilityin driving can be improved.

[0054] Preferable examples of the chalcogenide include SiO_(x) (1≦x≦2),AlO_(x) (1≦x≦1.5), SiON and SiAlON. Preferable examples of the metalhalide include LiF, MgF₂, CaF₂ and fluorides of rare earth metals.Preferable examples of the metal oxide include Cs₂O, Li₂O, MgO, SrO, BaOand CaO.

[0055] In the organic EL device of the present invention, it ispreferable that a mixed region of an electron transmitting compound anda reducing dopant or a mixed region of a hole transmitting compound andan oxidizing dopant is disposed on the surface of at least one of thepair of electrodes prepared as described above. Due to the mixed regiondisposed on the surface of the pair of electrodes, the electrontransmitting compound is reduced to form an anion and injection andtransportation of electrons from the mixed region into the lightemitting medium can be facilitated. The hole transmitting compound isoxidized to form a cation and injection and transportation of holes fromthe mixed region into the light emitting medium is facilitated.Preferable examples of the oxidizing dopant include various types ofLewis acid and acceptor compounds. Preferable examples of the reducingdopant include alkali metals, compounds of alkali metals, alkaline earthmetals, rare earth metals and compounds of these metals.

[0056] In the organic EL device, to achieve efficient light emission, itis preferable that at least one face of the device is sufficientlytransparent in the wave length region of the emitted light. It ispreferable that the substrate is also transparent. The transparentelectrode is disposed in accordance with vapor deposition or sputteringusing the above conductive material in a manner such that the prescribedtransparency is surly obtained. It is preferable that the electrodedisposed on the light emitting face has a transmittance of light of 10%or greater. The substrate is not particularly limited as long as thesubstrate has sufficient mechanical strength and strength at hightemperatures and is transparent. Glass substrates or transparent filmsof resins may be used. Example of the transparent films of resinsinclude films of polyethylene, ethylene-vinyl acetate copolymers,ethylene-vinyl alcohol copolymers, polypropylene, polystyrene,polymethyl methacrylate, polyvinyl chloride, polyvinyl alcohol,polyvinyl butyral, nylon, polyether ether ketones, polsulfones,polyether sulfones, tetrafluoroethylene-perfluoroalkyl vinyl ethercopolymers, polyvinyl fluoride, tetrafluoroethylene-ethylene copolymers,tetrafluoroethylene-hexafluoropropylene copolymers,polychlorotrifluoro-ethylene, polyvinylidene fluoride, polyesters,polycarbonates, polyurethanes, polyimides, polyether imides, polyimidesand polypropylene.

[0057] Each layer of the organic EL device of the present invention canbe formed suitably in accordance with a dry process of film formationsuch as vacuum vapor deposition, sputtering, plasma plating and ionplating or a wet process of film formation such as spin coating, dippingand flow coating. The thickness of the film is not particularly limited.However, it is necessary that the thickness be set at a suitable value.When the thickness is greater than the suitable value, a high voltagemust be applied to obtain a prescribed output of light and theefficiency decreases. When the thickness is smaller than the suitablevalue, pin holes are formed and a sufficient luminance cannot beobtained even when the electric field is applied. In general, thesuitable range of the thickness is 5 nm to 10 μm. A thickness in therange of 10 nm to 0.2 μm is preferable.

[0058] When the device is produced in accordance with a wet process,materials forming each layer are dissolved or dispersed in a suitablesolvent such as ethanol, chloroform, tetrahydrofuran and dioxane and afilm is formed from the solution or the suspension. The solvent is notparticularly limited. In any organic thin layer, suitable resins andadditives may be used to improve the property to form a film and toprevent formation of pin holes. Examples of the resin which can be usedinclude insulating resins such as polystyrene, polycarbonates,polyarylates, polyesters, polyamides, polyurethanes, polysulfones,polymethyl methacrylate, polymethyl acrylate and cellulose, copolymersderived from these resins, photoconductive resins such aspoly-N-vinylcarbazole and polysilane and conductive resins such aspolythiophene and polypyrrol. Examples of the additive includeantioxidants, ultraviolet light absorbents and plasticizers.

[0059] As described above, when the compound of the present invention isused for the organic layer of the organic EL device, the organic ELdevice exhibiting an excellent purity of color and a high efficiency oflight emission, having a long life and emitting red light can beobtained.

[0060] The organic EL device of the present invention can be used for aplanar light emitting member such as a flat panel display of walltelevisions, a back light for copiers, printers and liquid crystaldisplays, a light source of instruments, display panels and a markerlight.

[0061] The present invention will be described more specifically withreference to Synthesis Examples and Examples in the following.

SYNTHESIS EXAMPLE 1 (COMPOUND A-1)

[0062] 3,10- and3,11-Bisdiphenylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene wassynthesized via the reaction route shown in the following:

(A) Synthesis of 3,10- and3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthenes

[0063] In accordance with the J. B. Allen's process, 3,10- and3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthenes (7) weresynthesized using acenaphthenequinone (1) as the starting material via7,14-diphenylacenaphtho[1,2-k]fluoranthene (6). The structures of 3,10-and 3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthenes wereidentified from FD-MS (the field desorption mass spectra) and the ¹H-NMRspectra. The chemical shifts in ¹H-NMR agreed with the measured valuesreported by Allen (J. D. Debad, A. I. Bard, J. Chem. Soc., Vol. 120,2476 (1998)).

(B) Synthesis of 3,10- and3,11-diphenylamino-7,14-diphenylacenaphthofluoranthenes (Compound A-1)

[0064] Into 150 ml of toluene, 3.56 g (5.6 mmole) of 3,10- and3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthenes (7), 1.89 g(11.2 mmole) of diphenylamine, 0.06 g (0.3 mmole) of palladium acetate,0.22 g (1.1 mmole) of tri-tert-butylphosphine and 1.51 g (14.0 mmole) ofsodium tert-butoxide were dissolved at the room temperature and thereaction was allowed to proceed for 6 hours while the mixture wasrefluxed under heating. The resultant reaction mixture was filtered. Thefiltrate was concentrated and 4.8 g of a red orange powdery solid wasobtained. After the solid was dissolved in toluene, the solution wasfractionated in accordance with the column chromatography using a columnpacked with silica gel and 4.1 g of the main component was obtained. Themain component was confirmed to be 3,10- and3,11-diphenylamino-7,14-diphenylacenaphthofluoranthenes (Compound A-1)from FD-MS (812) and the structure of Compound (7). Precipitates in thereaction mixture separated by the filtration was washed with acetone andwater and dried and 0.6 g of a powdery solid was obtained. The obtainedsolid was confirmed to have the same structure as that of the productobtained from the filtrate from FD-MS (812) and the ¹H-NMR spectrum.

[0065] Similarly, Compound A-16 (Synthesis Example 2), Compound B-15(Synthesis Example 3), Compound A-8 (Synthesis Example 4), Compound B-18(Synthesis Example 5) and Compound B-17 (Synthesis Example 6) which arecompounds of 3,10- and3,11-diamino-7,14-diphenylacenaphtho[1,2-k]fluoranthenes weresynthesized via the reaction routes shown in the following:

SYNTHESIS EXAMPLE 2 (COMPOUND A-16)

[0066] The reaction was conducted in accordance with the same proceduresas those conducted in Synthesis Example 1 (B) except that 2.31 g (11.7mmole) of p,p′-ditolylamine was used in place of diphenylamine. Afterthe reaction was completed, the reaction mixture was filtered. Thefiltrate was washed with water and concentrated and a red powdery solidwas obtained. The obtained solid was fractionated in accordance with thecolumn chromatography using a column packed with silica gel and 2.9 g ofthe main component having a high purity was obtained. The main componentwas confirmed to be Compound A-16 from FD-MS (868).

SYNTHESIS EXAMPLE 3 (COMPOUND B-15)

[0067] The reaction was conducted in accordance with the same proceduresas those conducted in Synthesis Example 1 (B) except that 2.27 g (11.7mmole) of iminostilbene was used in place of diphenylamine. After thereaction was completed, the product precipitated in the reaction mixturewas separated, repeatedly washed with acetone and water and dried and3.4 g of a red orange powdery solid was obtained. The obtained solid wasdissolved in tetrahydrofuran and fractionated in accordance with thethin layer chromatography using a thin layer of silica gel and 2.3 g ofthe main component having a high purity was obtained. The main componentwas confirmed to be Compound B-15 from FD-MS (862).

SYNTHESIS EXAMPLE 4 (COMPOUND A-8)

[0068] The reaction was conducted in accordance with the same proceduresas those conducted in Synthesis Example 1 (B) except that 1.0 g (11.7mmole) of piperidine was used in place of diphenylamine. After thereaction was completed, the reaction mixture was filtered. The filtratewas washed with water and concentrated and a red powdery solid wasobtained. The obtained solid was dissolved in toluene and fractionatedin accordance with the column chromatography using a column packed withsilica gel and 2.1 g of the main component having a high purity wasobtained. The main component was confirmed to be Compound A-8 from FD-MS(644).

SYNTHESIS EXAMPLE 5 (COMPOUND B-18)

[0069] The reaction was conducted in accordance with the same proceduresas those conducted in Synthesis Example 1 (B) except that 1.96 g (11.7mmole) of carbazole was used in place of diphenylamine. After thereaction was completed, the product precipitated in the reaction mixturewas separated, repeatedly washed with acetone and water and dried and3.8 g of a red orange powdery solid was obtained. The obtained solid wasdissolved in tetrahydrofuran and fractionated in accordance with thethin layer chromatography using a thin layer of silica gel and 2.0 g ofthe main component having a high purity was obtained. The main componentwas confirmed to be Compound B-18 from FD-MS (808).

SYNTHESIS EXAMPLE 6 (COMPOUND B-17)

[0070] The reaction was conducted in accordance with the same proceduresas those conducted in Synthesis Example 1 (B) except that 2.33 g (11.7mmole) of phenothiazine was used in place of diphenylamine. After thereaction was completed, the reaction mixture was filtered. The filtratewas washed with water, concentrated and dried and 4.2 g of a orangepowdery solid was obtained. The obtained solid was dissolved in tolueneand fractionated in accordance with the thin layer chromatography usinga layer of silica gel and 2.6 g of the main component having a highpurity was obtained. The main component was confirmed to be CompoundB-17 from FD-MS (872).

SYNTHESIS EXAMPLE 7 (COMPOUND A-4)

[0071] Compound A-4 was synthesized via the reaction route shown in thefollowing:

[0072] In the synthesis of Compound (8), the reaction mixture wasexamined in accordance with the thin layer chromatography and thereaction was allowed to continue until the spot of Compound (6)disappeared. After the reaction was completed, the reaction mixture waswashed with a 0.1N aqueous solution of sodium hydroxide, concentratedand fractionated in accordance with the column chromatography using acolumn packed with silica gel and Compound (8) was obtained.

[0073] The reaction was conducted in accordance with the same proceduresas those conducted in Synthesis Example 1 (B) except that 3.12 g (5.6mmole) of Compound (8) was used in place of Compound (7) and 0.51 g(11.5 mmole) of piperidine was used in place of diphenylamine. The solidobtained by the reaction was dissolved in toluene and fractionated inaccordance with the column chromatography using a column packed withsilica gel and 2.2 g of Compound (9) having a high purity was obtained.

[0074] Compound (9) in an amount of 5.61 g (10.0 mmole) was dissolvedinto 30 ml of dimethylformamide. To the obtained solution, 1.68 g (11.0mmole) of phosphorus oxychloride was added and the mixture was refluxedunder heating. After the reaction was completed, the reaction mixturewas filtered and the filtrate was fractionated in accordance with thecolumn chromatography using a column packed with silica gel and 4.0 g ofthe main component having a high purity was obtained. The main componentwas confirmed to be Compound (10) from FD-MS (589).

[0075] Compound (10) in an amount of 4.7 g (8.0 mmole) was reacted with0.7 g (10.6 mmole) of malonitrile. The reaction product precipitated inthe reaction mixture was separated and dissolved in tetrahydrofuran. Theobtained solution was fractionated in accordance with the thin layerchromatography using a thin layer of silica gel and 3.6 g of red orangecrystals having a high purity were obtained. The crystals were confirmedto be Compound A-4 from FD-MS (637).

SYNTHESIS EXAMPLE 8 (COMPOUND A-14)

[0076] Compound A-14 was synthesized via the reaction route shown in thefollowing (S. H. Tucker, J. Chem. Soc., 1462 (1958)):

SYNTHESIS EXAMPLE 9 (COMPOUND A-6)

[0077] Compound A-6 was synthesized via the reaction route shown in thefollowing:

SYNTHESIS EXAMPLE 10 (COMPOUND B-5)

[0078] Compound B-5 was synthesized via the reaction route shown in thefollowing (Beil. 5(3) 2278):

SYNTHESIS EXAMPLE 11 (COMPOUND A-12)

[0079] Compound A-12 was synthesized via the reaction route shown in thefollowing:

SYNTHESIS EXAMPLE 12

[0080] A composition containing3,10-bisdiphenylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene and3,11-bisdiphenylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene in aratio of the amounts by mole in the range of 20:80 to 30:70 wassynthesized via the reaction route shown in the following:

(A) Synthesis of a Composition (18) Containing 3,10- and3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthenes in a Ratio ofthe Amounts by Mole of 22:78

[0081] The solution portion of the reaction mixture obtained inSynthesis Example 1 (A) was concentrated, dissolved in tetrahydrofuranand recrystallized and the formed precipitates were removed. Thesolution portion was concentrated and a dibromo compound was obtained.This dibromo compound was confirmed to be a composition containing 3,10-and 3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthenes in a ratioof the amounts by mole of 22:78 from the ¹H-NMR spectrum.

(B) Synthesis of a Composition Containing 3,10- and3,11-bisdiphenylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthenes in aRatio by the Amounts by Mole in the Range of 20:80 to 30:70

[0082] Into 100 ml of toluene, 5.00 g (7.9 mmole) of the compositioncontaining 3,10- and3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthenes in a ratio ofthe amounts by mole of 22:78 (18), 2.78 g (16.5 mmole) of diphenylamine,0.09 g (0.09 mmole) of palladium acetate, 0.44 g (2.2 mmole) oftri-tert-butylphosphine and 2.12 g (19.6 mmole) of sodium tert-butoxidewere dissolved and the reaction was allowed to proceed for 6 hours whilethe mixture was refluxed under heating. After the reaction wascompleted, the reaction mixture was filtered. The filtrate wasconcentrated and fractionated in accordance with the columnchromatography using a column packed with silica gel and 6.20 g of a redorange powdery solid was obtained. This solid was confirmed to be acomposition containing3,10-bisdiphenylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene and3,11-bisdiphenylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene in aratio of the amounts by mole in the range of 20:80 to 30:70 from FD-MS(812) and the ¹H-NMR spectrum (H: 400 MHz; the solvent of themeasurement: DMSO (120° C.); shown in FIG. 1).

SYNTHESIS EXAMPLE 13

[0083] 5,12- and/or5,13-Bisdiphenylamino-9,16-diphenylfluorantheno[8,9-a]aceanthryleneswere synthesized via the reaction route shown in the following:

(A) Synthesis of 9,16-diphenylfluorantheno[8,9-a]aceanthrylene (19)

[0084] With reference to the Bandyopadhyai's process,9,16-diphenylfluorantheno[8,9-a]aceanthrylene was synthesized by thereaction of 1,3-diphenylcyclopenta[a]aceanthrylen-2-one andacenaphthylene using aceanthrylenequinone as the starting material[Indian J. Chem., Vol. 21B, 91 (1982)].

(B) Synthesis of 5,12- and/or5,13-dibromo-9,16-diphenylfluorantheno[8,9-a]aceanthrylene (20)

[0085] Into 240 ml of methylene chloride, 4.00 g (7.6 mmole) of9,16-diphenylfluorantheno[8,9-a]aceanthrylene (19) was dissolved. Whilethe obtained mixture was refluxed under heating, 18.0 ml of a 1Mmethylene chloride solution of bromine was added dropwise and thereaction was allowed to proceed for 2 hours. The resultant reactionmixture was washed with an aqueous solution of sodium hydroxide and purewater and concentrated and 5.06 g of a yellow brown powdery solid wasobtained. The solid was confirmed to be5,12-dibromo-9,16-diphenylfluorantheno[8,9-a]aceanthrylene and/or5,13-dibromo-9,16-diphenylfluorantheno[8,9-a]aceanthrylene from FD-MS(686) and the ¹H-NMR spectrum.

(C) Synthesis of 5,12- and/or5,13-bisdiphenylamino-9,16-diphenylfluorantheno[8,9-a]aceanthrylene

[0086] Into 200 ml of toluene, 5.00 g (7.4 mmole) of 5,12- and/or5,13-dibromo-9,16-diphenylfluorantheno[8,9-a]aceanthrylene (20), 2.75 g(16.2 mmole) of diphenylamine, 0.09 g (0.4 mmole) of palladium acetate,0.43 g (2.2 mmole) of tri-tert-butylphosphine and 2.05 g (20.6 mmole) ofsodium tert-butoxide were dissolved and the reaction was allowed toproceed for 5 hours while the mixture was refluxed under heating. Afterthe reaction was completed, the reaction mixture was filtered. Thefiltrate was concentrated and fractionated in accordance with the columnchromatography using a column packed with silica gel and 4.27 g of ablack purple powdery solid of the main component was obtained. The maincomponent was confirmed to be 5,12- and/or5,13-bisdiphenylamino-9,16-diphenylfluorantheno[8,9-a]aceanthrylene fromFD-MS (862) and the ¹H-NMR spectrum (H: 400 MHz; the solvent of themeasurement: DMSO (120° C.); shown in FIG. 2).

SYNTHESIS EXAMPLE 14

[0087] 3,11- and/or3,12-Bisdiphenylamino-7,16-diphenylfluorantheno[8,9-k]fluoranthene wassynthesized via the reaction route shown in the following:

(A) Synthesis of 2,5-diphenylfluorantheno[11′,12′-3,4]furan (21)

[0088] In accordance with the N. Campbell's process [J. Chem. Soc., 1555(1949)], 2,5-diphenylfluorantheno[11′,12′-3,4]furan (21) was synthesizedby the reaction of 7,8-dimethylacenaphthene-7,8-diol which wassynthesized in accordance with the S. H. Tucker's process [J. Chem.Soc., 1462 (1958)] and trans-1,2-dibenzoylethylene.

(B) Synthesis of 7,16-diphenylfluorantheno[8,9-k]fluoranthene (22)

[0089] Into a mixed solvent containing 500 ml of xylene and 660 ml ofmethylene chloride, 5.00 g (12.7 mmole) of2,5-diphenylfluorantheno[11′,12′-3,4]furan (21) and 3.86 g (19.0 mmole)of acenaphthylene were added and the mixture was refluxed under heatingfor 3 hours. The solution was cooled and 16.0 ml of a 1M methylenechloride solution of BBr₃ was added dropwise to the cooled solution. Theobtained solution was heated at 60° C. for 4 hours. The resultantreaction mixture was washed with an aqueous solution of sodiumhydrogencarbonate and pure water, concentrated and purified inaccordance with the column chromatography using a column packed withsilica gel and 3.20 g of yellow crystals were obtained. The crystalswere confirmed to be 7,16-diphenylfluorantheno[8,9-k]fluoranthene (22)from FD-MS (528) and the ¹H-NMR spectrum.

(C) Synthesis of 3,11- and/or3,12-dibromo-7,16-diphenylfluorantheno[8,9-k]fluoranthene (23)

[0090] Into 230 ml of methylene chloride, 2.30 g (4.3 mmole) of7,16-diphenylfluorantheno[8,9-k]fluoranthene (22) was dissolved. Whilethe obtained solution was refluxed under heating, 9.0 ml of a 1Mmethylene chloride solution of bromine was added dropwise to thesolution and then the reaction was allowed to proceed for 2 hours. Theresultant reaction mixture was washed with an aqueous solution of sodiumhydroxide and pure water and concentrated and 3.06 g of a light yellowbrown crystals were obtained. The crystals were confirmed to be 3,11-and/or 3,12-dibromo-7,16-diphenylfluorantheno[8,9-k]fluoranthene (23)from FD-MS (686) and the ¹H-NMR spectrum.

(D) Synthesis of 3,11- and/or3,12-bisdiphenylamino-7,16-diphenylfluorantheno[8,9-k]fluoranthene

[0091] Into 120 ml of toluene, 3.92 g (5.7 mmole) of 3,11- and/or3,12-dibromo-7,16-diphenylfluorantheno[8,9-k]fluoranthene (23), 2.03 g(12.0 mmole) of diphenylamine, 0.07 g (0.07 mmole) of palladium acetate,0.33 g (1.7 mmole) of tri-tert-butylphosphine and 1.56 g (14.4 mmole) ofsodium tert-butoxide were dissolved and the reaction was allowed toproceed for 6 hours while the mixture was refluxed under heating. Afterthe reaction was completed, the reaction mixture was filtered. Thefiltrate was purified in accordance with the column chromatography usinga column packed with silica gel and 4.27 g of a orange powdery crystalswere obtained. The crystals were confirmed to be 3,11- and/or3,12-bisdiphenylamino-7,16-diphenylfluorantheno[8,9-k]fluoranthene fromFD-MS (862) and the ¹H-NMR spectrum (H: 400 MHz; the solvent of themeasurement: DMSO (120° C.); shown in FIG. 3).

SYNTHESIS EXAMPLE 15

[0092] A composition containing3,10-bisditolylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene and3,11-bisditolylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene in aratio of the amounts by mole in the range of 80:20 to 90:10 wassynthesized.

(A) Synthesis of a Composition (18) Containing 3,10- and3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthenes

[0093] The solution portion of the reaction mixture obtained inSynthesis Example 1 (A) was concentrated, dissolved entirely intetrahydrofuran and recrystallized and the formed precipitates wereremoved. The solution portion was concentrated and a dibromo compoundwas obtained. This dibromo compound was confirmed to be a compositioncontaining 3,10- and3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthenes containing in aratio of the amounts by mole in the range of 80:20 to 90:10 from the¹H-NMR spectrum.

(B) Synthesis of a Composition Containing 3,10- and3,11-bisditolylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthenes in aRatio of the Amounts by Mole in the Range of 80:20 to 90:10

[0094] In accordance with the same procedures as those conducted inSynthesis Example 12 (B) except that di-p,p-tolylamine was used in placeof diphenylamine, a composition (A-16) containing 3,10- and3,11-bisditolylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthenes in aratio of the amounts by mole in the range of 80:20 to 90:10 wassynthesized.

SYNTHESIS EXAMPLE 16

[0095] A composition containing3,10-bisdiphenylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene and3,11-bisdiphenylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene in aratio of the amounts by mole in the range of 80:20 to 90:10 wassynthesized.

(A) Synthesis of a Composition (18) Containing 3,10- and3,11-dibromo-7,14-diphenylacenaphtho[1,2-k]fluoranthenes

[0096] The composition containing the dibromo compounds was obtained inaccordance with the same procedures as those conducted in SynthesisExample 15 (A).

(B) Synthesis of a Composition (A-1) Containing 3,10- and3,11-bisdiphenylamino-7,14-diphenyloacenaphtho[1,2-k]fluoranthenes in aRatio of the Amounts by Mole in the Range of 80:20 to 90:10

[0097] In accordance with the same procedures as those conducted inSynthesis Example 12 (B) using the composition obtained above in (A), acomposition containing3,10-bisdiphenylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene and3,11-bisdiphenylamino-7,14-diphenylacenaphtho[1,2-k]fluoranthene in aratio of the amounts in mole in the range of 80:20 to 90:10 wassynthesized.

EXAMPLE 1

[0098] On a cleaned glass plate having an ITO electrode, the followingcompound (H232) as the hole injecting material was vapor deposited sothat a film having a thickness of 60 nm was formed.

[0099] Then, the following compound (NPD) as the hole transportingmaterial was vapor deposited so that a film having a thickness of 20 nmwas formed.

[0100] Subsequently, an aluminum complex of 8-hydroxyquinoline (Alq) and3,10- and 3,11-diphenylamino-7,14-diphenylacenaphthofluoranthenes(Compound A-1) as the materials for the light emitting layer were vapordeposited so that a film containing 2.1% by mole of Compound A-1 andhaving a thickness of 50 nm was formed. The structure of Alq is shown inthe following:

[0101] An electron injecting layer was formed by vapor deposition of Alqalone so that the formed film had a thickness of 10 nm. A layer of aninorganic compound was formed on the electron injecting layer by vapordeposition of LiF so that the formed film had a thickness of 0.2 nm. Onthe thus formed layer, aluminum was vapor deposited so that an electrodehaving a thickness of 170 nm was formed and an organic EL device wasobtained. The vapor depositions for forming the above layers wereconducted under 10⁻⁶ Torr while the substrate was kept at the roomtemperature.

[0102] The light emitting property of this device was as follows: theluminance under application of a direct current of 5.5 V: 103 cd/m²; theefficiency of light emission: as high as 6.2 cd/A. The emitted light wasorange light having chromaticity coordinates of (0.56, 0.44). When thedevice was driven under a constant current at an initial luminance of500 cd/m², the half-life was as long as 2600 hours.

[0103] This example shows that an organic EL device exhibiting a highperformance can be obtained by using Compound A-1 as the dopingmaterial. The spectrum of the light emitted by the device was obtainedand found to be the same as the fluorescence spectrum of the dopingmaterial. Thus, it is shown that the doping material worked as thecenter of light emission.

COMPARATIVE EXAMPLE 1

[0104] An organic EL device was obtained in accordance with the sameprocedures as those conducted in Example 1 except that rubrene was vapordeposited in place of Compound A-1 so that a film containing 4.0% bymole of rubrene was formed.

[0105] The light emitting property of this device was as follows: theluminance under application of a direct current of 5.5 V: 105 cd/m²; theefficiency of light emission: 7.6 cd/A. However, the emitted light wasyellow light having chromaticity coordinates of (0.50, 0.50). Thehalf-life was 1000 hours when the device was driven under a constantcurrent at an initial luminance of 500 cd/m² and shorter than that ofthe device of Example 1.

Comparative Example 2

[0106] An organic EL device was obtained in accordance with the sameprocedures as those conducted in Example 1 except thatfluorantheno[8,9-k]fluoranthene described in Japanese Patent ApplicationLaid-Open No. Heisei 11(1999)-40360 was vapor deposited in place ofCompound A-1 so that a film containing 2% by mole of this fluoranthenewas formed.

[0107] The light emitting property of this device was as follows: theluminance under application of a direct current of 5.5 V: 35 cd/m²; theefficiency of light emission: 3.0 cd/A. The emitted light was yellowgreen light. The half-life was as short as 300 hours when the device wasdriven under a constant current at an initial luminance of 500 cd/m².

Comparative Example 3

[0108] An organic EL device was obtained in accordance with the sameprocedures as those conducted in Example 1 except that7,14-diphenylacenaphtho[1,2-k]fluoranthene described in Japanese PatentApplication Laid-Open No. Heisei 11(1999)-168445 was vapor deposited inplace of Compound A-1 so that a film containing 2% by mole of thisfluoranthene was formed.

[0109] The light emitting property of this device was as follows: theluminance under application of a direct current of 6 V: 69 cd/m²; theefficiency of light emission: 1.3 cd/A. The emitted light was yellowgreen light. The efficiency was smaller than that of a device in whichAlq alone was used as the light emitting material. The half-life was asshort as 400 hours when the device was driven under a constant currentat an initial luminance of 500 cd/m². When the spectrum of the lightemitted by the device was obtained, the spectrum did not agree with thefluorescence spectrum of the doping material. Thus, it was found thatthe above compound did not emit light and the yellow green light wasemitted from Alq. The doping material did not work as the light emittingmaterial.

EXAMPLE 2 TO 11

[0110] Organic EL devices were obtained in accordance with the sameprocedures as those conducted in Example 1 except that compounds shownin Table 1 were vapor deposited in place of Compound A-1.

[0111] The light emitting properties of these devices were obtained inaccordance with the same methods as those used in Example 1. The voltageapplied in the measurements, the luminance, the efficiency of lightemission, the color of the emitted light and the half-life when thedevice was driven under a constant current at an initial luminance of500 cd/m² are shown in Table 1.

EXAMPLE 12

[0112] An organic EL device was obtained in accordance with the sameprocedures as those conducted in Example 1 except that the compositioncontaining the prescribed relative amounts of the isomers which wasobtained in Synthesis Example 12 (Compound A-1) was used for the lightemitting layer in a concentration of 100% and Alq was not used.

[0113] The light emitting property of this device was as follows: theluminance under application of a direct current of 4.5 V: 80 cd/m²; theefficiency of light emission: 3.5 cd/A. The half-life was as long as2100 hours when the device was driven under a constant current at aninitial luminance of 500 cd/m². The device had a longer life than thatof the device of Example 1 and can be used also as the main lightemitting material.

EXAMPLE 13

[0114] An organic EL device was obtained in accordance with the sameprocedures as those conducted in Example 1 except that the compositioncontaining the prescribed relative amounts of the isomers which wasobtained in Synthesis Example 15 (Compound A-16) was used for the lightemitting layer in place of Compound A-1.

[0115] The light emitting property of this device was as follows: theluminance under application of a direct current of 5.5 V: 94 cd/m²; theefficiency of light emission: 5.94 cd/A. The emitted light was reddishorange light having chromaticity coordinates of (0.60, 0.39). Thehalf-life was as long as 3200 hours when the device was driven under aconstant current at an initial luminance of 500 cd/m².

EXAMPLE 14

[0116] An organic EL device was obtained in accordance with the sameprocedures as those conducted in Example 1 except that the compositioncontaining the prescribed relative amounts of the isomers which wasobtained in Synthesis Example 16 (Compound A-1) was used for the lightemitting layer in place of Compound A-1.

[0117] The light emitting property of this device was as follows: theluminance under application of a direct current of 6 V: 100 cd/m²; theefficiency of light emission: 4.75 cd/A. The emitted light hadchromaticity coordinates of (0.58, 0.42). The half-life was as long as1800 hours when the device was driven under a constant current at aninitial luminance of 500 cd/m². The light having more reddish color thanthat of the light emitted in Example 1 could be emitted by using theabove compound. This result was obtained because the compositioncontained a greater amount of the isomer3,11-bisdiphenylamino-7,14-diphenylacenaphtho[12-k]fluoranthene whichcould emit light having a longer wavelength. TABLE 1 Efficiency Volt-Lumi- of light Color of Half- Comp- age nance emission emitted lifepound (V) (cd/m²) (cd/A) light (hour) Example 2 A-2 5.5 140 5.7 reddish2800 orange Example 3 A-8 5.8 120 3.6 orange 2100 Example 4 A-14 5.2 1206.1 red 2700 Example 5 A-16 6.0 170 4.7 reddish 3100 orange Example 6B-3 6.0 160 3.2 reddish 1900 orange Example 7 B-15 5.5 130 2.8 orange1800 Example 8 B-17 5.8 110 2.0 reddish 1700 orange Example 9 B-18 6.1120 2.8 reddish 2000 orange Example 10 A-4 7.2 110 3.7 red 1000 Example11 B-5 6.0 120 6.7 yellowish 1800 green

[0118] Industrial Applicability

[0119] As described above in detail, the organic electroluminescencedevice of the present invention which utilizes the compound selectedfrom the compounds represented by general formulae [1] to [18] emitsyellowish to reddish light, exhibits an excellent purity of color and ahigh efficiency of light emission and has a long life.

[0120] Therefore, the organic electroluminescence device of the presentinvention is advantageously used as a light source such as a planarlight emitting member of televisions and a back light of displays.

1. An organic electroluminescence device which comprises an organiclayer disposed between at least one pair of electrodes, wherein theorganic layer comprises a compound having a fluoranthene skeletonstructure substituted at least with an amine group or an alkenyl group.2. An organic electroluminescence device according to claim 1, whereinsaid compound is a compound selected from compounds represented by thefollowing general formulae [1] to [18]:

wherein X¹ to X²⁰ each independently represents hydrogen atom, a linear,branched or cyclic alkyl group having 1 to 20 carbon atoms, a linear,branched or cyclic alkoxy group having 1 to 20 carbon atoms, asubstituted or unsubstituted aryl group having 6 to 30 carbon atoms, asubstituted or unsubstituted aryloxy group having 6 to 30 carbon groups,a substituted or unsubstituted arylamino group having 6 to 30 carbonatoms, a substituted or unsubstituted alkylamino group having 1 to 30carbon atoms, a substituted or unsubstituted arylalkylamino group having7 to 30 carbon atoms or a substituted or unsubstituted alkenyl groupshaving 8 to 30 carbon atoms; a pair of adjacent groups represented by X¹to X²⁰ and a pair of adjacent substituents to groups represented by X¹to X²⁰ may form a cyclic structure in combination; when a pair ofadjacent substituents are aryl groups, the pair of substituents may be asingle group; and at least one of substituents represented by X¹ toX^(i), i representing a number of 12 to 20, comprises an amine group oran alkenyl group;

wherein R¹ to R⁴ each independently represent an alkyl group having 1 to20 carbon atoms or a substituted or unsubstituted aryl group having 6 to30 carbon atoms; in one or both of a pair of groups represented by R¹and R² and a pair of groups represented by R³ and R⁴, the groups formingthe pair may be bonded through —O— or —S—; R⁵ to R¹⁶ represents hydrogenatom, a linear, branched or cyclic alkyl group having 1 to 20 carbonatoms, a linear, branched or cyclic alkoxy group having 1 to 20 carbonatoms, a substituted or unsubstituted aryl group having 6 to 30 carbonatoms, a substituted or unsubstituted aryloxy group having 6 to 30carbon groups, a substituted or unsubstituted arylamino group having 6to 30 carbon atoms, a substituted or unsubstituted alkylamino grouphaving 1 to 30 carbon atoms, a substituted or unsubstitutedarylalkylamino group having 7 to 30 carbon atoms or a substituted orunsubstituted alkenyl groups having 8 to 30 carbon atoms; a pair ofadjacent groups represented by R⁵ to R¹⁶ and a pair of adjacentsubstituents to groups represented by R5 to R¹⁶ may form a cyclicstructure in combination; and at least one of substituents representedby R⁵ to R¹⁶ comprises an amine group or an alkenyl group.
 3. An organicelectroluminescence device according to any of claims 1 and 2, whereinthe organic layer is at least one of a hole transporting layer and alight emitting layer.
 4. An organic electroluminescence device accordingto claim 1, wherein the organic layer comprises 1 to 70% by weight ofsaid compound which is selected from compounds represented by generalformulae [1] to [18].
 5. An organic electroluminescence device accordingto any of claims 1 to 4, wherein a layer of an inorganic compound isdisposed between the organic layer and the electrode.
 6. An organicelectroluminescence device according to any of claims 1 to 5, whichemits reddish light.
 7. An organic electroluminescence device accordingto claim 1, wherein the organic layer comprises said compound andisomers thereof.
 8. An organic electroluminescence device according toclaim 7, wherein, among said compound and the isomers thereof, a ratioof an amount by mole of an isomer which can emit light having a longerwavelength to an amount by mole of an isomer which can emit light havinga shorter wave is in a range of 90:10 to 60:40.
 9. An organicelectroluminescence device according to claim 7, wherein, among saidcompound and the isomers thereof, a ratio of an amount by mole of anisomer represented by general formula [17] to an amount by mole of anisomer represented by general formula [18] is in a range of 90:10 to60:40.
 10. A novel compound represented by any of the following generalformulae [1] to [18]:

wherein X¹ to X²⁰ each dependently represents hydrogen atom, a linear,branched or cyclic alkyl group having 1 to 20 carbon atoms, a linear,branched or cyclic alkoxy group having 1 to 20 carbon atoms, asubstituted or unsubstituted aryl group having 6 to 30 carbon atoms, asubstituted or unsubstituted aryloxy group having 6 to 30 carbon groups,a substituted or unsubstituted arylamino group having 6 to 30 carbonatoms, a substituted or unsubstituted alkylamino group having 1 to 30carbon atoms, a substituted or unsubstituted arylalkylamino group having7 to 30 carbon atoms or a substituted or unsubstituted alkenyl groupshaving 8 to 30 carbon atoms; a pair of adjacent groups represented by X¹to X²⁰ and a pair of adjacent substituents to groups represented by X¹to X²⁰ may form a cyclic structure in combination; when a pair ofadjacent substituents are aryl groups, the pair of substituents may be asingle group; and at least one of substituents represented by X¹ toX^(i), i representing a number of 12 to 20, comprises an amine group oran alkenyl group;

wherein R¹ to R⁴ each independently represent an alkyl group having 1 to20 carbon atoms or a substituted or unsubstituted aryl group having 6 to30 carbon atoms; in one or both of a pair of groups represented by R¹and R² and a pair of groups represented by R³ and R⁴, the groups formingthe pair may be bonded through —O— or —S—; R⁵ to R¹⁶ represents hydrogenatom, a linear, branched or cyclic alkyl group having 1 to 20 carbonatoms, a linear, branched or cyclic alkoxy group having 1 to 20 carbonatoms, a substituted or unsubstituted aryl group having 6 to 30 carbonatoms, a substituted or unsubstituted aryloxy group having 6 to 30carbon groups, a substituted or unsubstituted arylamino group having 6to 30 carbon atoms, a substituted or unsubstituted alkylamino grouphaving 1 to 30 carbon atoms, a substituted or unsubstitutedarylalkylamino group having 7 to 30 carbon atoms or a substituted orunsubstituted alkenyl groups having 8 to 30 carbon atoms; a pair ofadjacent groups represented by R⁵ to R¹⁶ and a pair of adjacentsubstituents to groups represented by R⁵ to R¹⁶ may form a cyclicstructure in combination; and at least one of substituents representedby R⁵ to R¹⁶ comprises an amine group or an alkenyl group.